Effect of lairage during 24 h of transport on the behavioural and physiological responses of sheep

The effects on the behavioural and physiological responses of sheep of providing vest, food and water (lairage) during 24 h of either road transport or stationary confinement (treatment) were investigated. Twenty-four hours of continuous treatment was compared with 12 h of treatment followed by either 12 h of lairage, 3 h of lairage or 3 h of food and water on the vehicle, followed by a second 12 h of treatment. A further group of sheep was kept as controls. The plasma cortisol concentration was increased at the start of the journey and after 24 h of continuous transport it was still greater than that in controls (P < 0.05). Apart from a mobilization of body energy reserves as indicated by raised plasma concentrations of free fatty acids after 12 h and beta-hydroxybutyrate after 24 h there was no evidence that the welfare of the sheep during the journey was compromised after a particular time. During the lairage and immediately after the second 12-h transport period, the sheep appeared to be hungry. Although sheep transported for 24 h without lairage drank more post transport than controls, there was no biochemical evidence of dehydration during the journey. The sheep lay down during the journey and there was no apparent difference between lairage treatments in the proportion of scans spent lying down during either the second 12-h treatment period or during the first 12 h post treatment. There were fewer potentially traumatic events during the second 12 h of the 24-h journey than during the first 12 h of the journey and no apparent effect of lairage during the journey on the frequency of potentially traumatic events during the second 12-h period of transport. There was evidence to suggest that a period of lairage during a 24-h journey can be beneficial in providing sheep with an opportunity to eat, drink and avoid the stressors associated with transport. However, providing hay and water on the vehicle during a 3-h stationary period as compared with unloading into a lairage cannot be recommended. Although sheep readily ate hay on the vehicle, they did not drink sufficient water. This resulted in dehydration and a greater plasma cortisol concentration during the remainder of the journey than. in those that had been lairaged for 12 h and a greater water intake post transport than in those given either no lairage or 12 h of lairage.